Invite time travelers to a party late? "I sat there a long time, no one came."

Stephen Hawking is near-universally recognized as a brilliant scientist, and one small facet of his complex genius is the rockstar ability to democratize scientific knowledge. It's becoming increasingly important as purveyors of pop culture continue to eschew acknowledgment and respect for the most basic scientific principles. Hollywood in particular has continued its marginalization of scientific knowledge with blatant disregard in recent films.

But Hawking acts like a great counter force against anti-intellectual movements. He takes complex scientific principles and explains them so the general public can understand and, more importantly, appreciate the science behind them. He inspires people to want to know more about Calabi–Yau manifolds and multiverses. That is why Stephen Hawking rocks our scientific world.

So I (and everyone around me) felt a consummate air of curiosity in the Paramount Theater lobby on June 16, as Dr. Hawking arrived for an appearance at the Seattle Science Festival. But what was everyone curious about? Was it Dr. Hawking's motor neuron disease? Or how his speech synthesizer works, perhaps?

The following are the press questions from Seattle-area colleagues that I read to Dr. Hawking at a press event before his main program. The 70-year-old scientist keynoted a Saturday night symposium that also featured Leroy Hood and Jack Horner, with Hawking discussing his life and Nobel aspirations among other topics.

What would it take to make time travel a reality, and how would that affect the present reality? (via Arik Korman, 95.7 KJR)

We are all travelling forward in time anyway. We can fast forward by going off in a rocket at high speed and return to find everyone on Earth much older or dead. Einstein's general theory of relativity seems to offer the possibility that we could warp space-time so much that we could travel back in time. However, it is likely that warping would trigger a bolt of radiation that would destroy the spaceship and maybe the space-time itself. I have experimental evidence that time travel is not possible. I gave a party for time-travelers, but I didn't send out the invitations until after the party. I sat there a long time, but no one came.

Horner and Hood at the symposium

Jack Horner entertained the audience by waxing about his work at Montana State University, where his goal is to use the tools of evolution to recreate the dinosaurs. The gist of the effort: his Montana labs are attempting what is known as "reverse evolution," creating a dinosaur from existing bird species such as the chicken. Horner points out that all life is interrelated, as species have long descended from one another with certain modifications.

So Horner's Montana lab is tweaking evolution's dialectic via complex procedures on embryos and making probes with extracted DNA. They then replace the probe to control the growth of "experimental atavisms"—long suppressed evolutionary dinosaur characteristics such as a long tail, three-fingered claws, and dinosaur teeth. Horner's goal is to grow the world's first "chickasaur." And he points out it's best to start out small because it's easier to catch if something goes wrong.

Leroy Hood's presentation touched on what he calls P4 medicine: predictive, preventative, personalized, and participatory. It is predictive because future medicine will draw from what will be a completed data set of the human genome in about ten years, and will make use of massive pools of digitized bio-information. "Preventative" because the approach to drugs will target discovery of illness via the use of such large repositories of digital genomic data. The P4 model should see the cost of medicine go down, allowing a focus on wellness from the continued mining of millions of data points for ongoing patient diagnoses. Each patient will have a unique genomic profile, so the approach can be tailored to each patient. Hood even imagines patient-driven social networks for individuals to share information on disease and wellness.

If M-theory is the only candidate for a complete theory of the universe, what's the best evidence that you think will be found to support the theory? Lacking that evidence, isn't M-theory just another kind of religion? (via Alan Boyle, MSNBC)

M-theory is the only theory that seems to have all the properties we would expect of a complete and consistent "history of everything," but that may just reflect our lack of imagination. If M-theory is correct, it predicts that every particle should have a super-partner. So far, we have not observed any super-partners, but the hope is that they will be found at the LHC. If they are discovered, it will be strong evidence for M-theory. On the other hand, it they are shown not to exist, that will be exciting, because we will learn something new.

How would you describe your quality of life? What do you miss most from before the onset of ALS? (via Arik Korman, 95.7 KJR)

Although I am severely disabled and on a ventilator, my quality of life is pretty good. I have been very successful in my scientific work, and have become one of the best known scientists in the world. I have three children and three grandchildren so far. I travel widely, have been to Antarctica, and have met the presidents of Korea, China, India, Ireland, Chile, and the United States. I have been down in a submarine and up on a zero-gravity flight, in preparation for the flight into space that I'm hoping to make on Virgin Galactic. Despite my disability, I have managed to do most things I want. My main regret is that it has prevented me from playing with my children and grandchildren as fully as I want.

John Gribben recently argued that we are almost certainly the only intelligent life in the Milky Way—do you think he's right or wrong, and why? Also, Seth Shostak argues that even if there are other intelligent civilizations out there, it's too late for us to keep quiet about our existence, because it's possible to pick up the signals we've sent out over the past seventy years. So, isn't it too late for us to keep quiet, and shouldn't we be thinking about upgrading our defenses against the alien hordes? (via Alan Boyle, MSNBC)

We think that life develops spontaneously on Earth, so it must be possible for life to develop on suitable planets elsewhere in the universe. But we don't know the probability that a planet develops life. If it is very low, we may be the only intelligent life in the galaxy. Another frightening possibility is intelligent life is not only common, but that it destroys itself when it reaches a stage of advanced technology.

Evidence that intelligent life is very short-lived is that we don't seem to have been visited by extra terrestrials. I'm discounting claims that UFOs contain aliens. Why would they appear only to cranks and weirdos? Do I believe that there is some government conspiracy to conceal the evidence and keep for themselves the advanced technology the aliens have? If that were the case, they aren't making much use of it. Further evidence that there isn't any intelligent life within a few hundred light years comes from the fact that SETI, the Search for Extra Terrestrial Life, hasn't picked up their television quiz shows. It is true that we advertise our presence by our broadcast. But given that we haven't been visited for four billion years, it isn't likely that aliens will come any time soon.